Vardenafil Hcl is a PDE5 inhibitor used for treating erectile dysfunction.Target: PDE5Vardenafil specifically inhibited the hydrolysis of cGMP by PDE5 with an IC50 of 0.7 nM (6.6 nM). In contrast, the IC50 of vardenafil for PDE1 was 180 nM; for PDE6, 11 nM; for PDE2, PDE3 and PDE4, more than 1000 nM. Relative to PDE5, the ratios of the IC50 for PDE1 were 257 (60), for PDE6 16 (7.4). Vardenafil significantly enhanced the SNP-induced relaxation of human trabecular smooth muscle at 3 nM (10 nM). Vardenafil also significantly potentiated both ACh-induced and transmural electrical stimulation-induced relaxation of trabecular smooth muscle [1]. Both vardenafil doses(10 mg or 20 mg) significantly enhanced the

[1]. Saenz de Tejada, I., et al., The phosphodiesterase inhibitory selectivity and the in vitro and in vivo potency of the new PDE5 inhibitor vardenafil. Int J Impot Res, 2001. 13(5): p. 282-90. [2]. Goldstein, I., et al., Vardenafil, a new phosphodiesterase type 5 inhibitor, in the treatment of erectile dysfunction in men with diabetes: a multicenter double-blind placebo-controlled fixed-dose study. Diabetes Care, 2003. 26(3): p. 777-83.